If only 2 arguments are passed to userprops.set(), assume the caller won't to

set the entire section/object all in one go. This is more intuitive than the
(still supported) userprops.set(section, null, object) syntax.

exec/load/userprops.js

@@ -44,6 +44,8 @@ function set(section, key, value, usernum)
 	var result;
 	if(!section)
 		result = file.iniSetAllObjects(value);
+	else if(value === undefined)
+		result = file.iniSetObject(section, key);
 	else if(!key)
 		result = file.iniSetObject(section, value);
 	else